Vertebrata Cuvier, 1812 - vertebrates Class Agnatha Cope, 1889 [paraphyletic] 1 Subclass †Pteraspidomorphi Goodrich, 1909 see Class Pteraspidomorphi Goodrich, 1909 2 Subclass Cephalaspidomorpha see Class Agnatha Cope, 1889 3 Order Myxiniformes incertae sedis [monotypic] - hagfishes